Study: Nationwide E85 Use Could Worsen Public Health

18 April 2007

Fleet-wide use of E85 in the United States could increase the number of respiratory-related deaths and hospitalizations, according to a new study by Stanford University professor Mark Jacobson. His findings are published online in the journal Environmental Science & Technology (ES&T).

Jacobson combined an air pollution/weather forecast model with future emission inventories, population data, and health effects data to examine the effect of converting from gasoline to E85 on cancer, mortality, and hospitalization in the US as a whole and Los Angeles in particular.

After accounting for projected improvements in gasoline and E85 vehicle emission controls, the study found that E85 may increase ozone-related mortality, hospitalization, and asthma by about 9% in Los Angeles (120 deaths/year with a range of 47-140/yr) and 4% in the US as a whole (185 deaths/yr with a range of 72-216/yr) relative to 100% gasoline.

E85 also increased hospitalization by about 650 and 990 in Los Angeles and the US, respectively, and asthma-related emergency-room visits by about 770 and 1,200 in Los Angeles and the US, respectively.

While the simulations found that E85 vehicles reduced atmospheric levels of benzene and butadiene—two carcinogens—compared to gasoline vehicles, the E85 vehicles increased levels of formaldehyde and acetaldehyde—two other carcinogens. As a result, cancer rates for E85 are likely to be similar to those for gasoline.

Due to its ozone effects, future E85 may be a greater overall public health risk than gasoline. However, because of the uncertainty in future emission regulations, it can be concluded with confidence only that E85 is unlikely to improve air quality over future gasoline vehicles. Unburned ethanol emissions from E85 may result in a global-scale source of acetaldehyde larger than that of direct emissions.

The projected health effects of E85 would be the same regardless of feedstock or process.

Mike: The USA is actually due for shortages of natural gas. The only thing that has kept us from noticing has been warm winters. There is a rush on to build LNG terminals and pipelines from the arctic. If you switch our cars over to NG you're just going to exacerbate the situation. Russia and the Middle east (Qatar) are the ones with the big NG reserves.

The U.S. actually peaked on NG production in the early 70s. Which means we never produced as much since. Lately we have been drilling wells in Oklahoma, Wyoming, Montana and elsewhere, that were not profitable before the rise in NG prices.

Many countries have abundant reserves of NG, but it is getting it to where it is used that is the problem. LNG tankers can explode and pipelines are expensive. You could turn it into methanol or other liquid fuels and ship it, but the investments in plant and equipment can be huge. Iran, Saudi Arabia, Iraq all have large NG reserves. It is the economics of creating these pipelines and facilities that holds things up. Running their own countries on NG works for now.

The most common numbers peg the U.S. as having about 3% of the conventional global reserves of NG. We may be the Saudi Arabia of coal, but certainly not of NG.

The actual risks associated with LNG tankers are far more modest than a movie like "Syriana" would have you believe. They tend not to "explode." New offloading terminals are being sited offshore, further reducing the risks LNG operations pose to local populations. At the same time, LNG operations are still somewhat expensive in terms of time, money and energy, so we have to consider that impact, as well as the traditional problem of being dependent on imported energy.

Regarding E85, this paper does not seem to address the most obvious solution, which is selective deployment.

This paper already shows that E85 is more dangerous in some places than others -- 9% worse outcomes in LA, versus 4% worse outcomes if used across the whole country. This implies that there are areas where the negative impacts are less than 4% -- some place has to be lower than the average to offset the places, like LA, that are higher than the average.

This article makes no mention of where those places are, or how much less bad the use of E85 might be there. Perhaps there are areas in which E85 creates zero difference, or even leads to improved public health outcomes?

At present, we have boutique fuels and varying blends across summer and winter. A similar approach could be taken to the deployment of E85 -- encourage its retailing only in areas where its widespread use does not create new problems.

Having looked through the text of the paper itself, it would seem to suggest that the widespread use of ethanol in the southeastern U.S. would be neutral to positive in most respects. This conclusion is based on their coarse-grained whole-U.S. analysis.

Why they did not run a fine-grained southeast-only analysis like they did for L.A., to see what the health effects of E85 would be if deployed only in that area, is beyond me. Maybe they did not want ethanol to look good.

you have got a great big boil right in the middle of the United States,
I am thinking of the super volcano at yellowstone in wyoming, surely
if it was lanced correctly the energy derived could supply the states
with all its needs , if you don´t then maybe its going to pop , and then
I am afraid the question of gas verses ethanol will become irrelevant!

You may have LNG tanker offshore facilities, but I doubt that a terrorist would play be the rules and stop at an offshore facility. At a 20 knot speed, they could make it quite a ways in before anything could be done.

I'm not a big fan of E85, but this "Study" is BS. There's not enough ethanol to run all the cars in the US at E10 let alone E85. Secondly, the robustness of it's conclusion is questionable. When you internally combust anything there's going to be unwanted products.

You are correct..we may never get to E85 anyway. That might not be desirable even if there were no health risks. We have to change the way we use fuel, period. I have long thought that the benzene in the environment from fossil fuels has been more harmful than anyone will admit. Conservation means the less we use now, the more we have for later. A pretty simple principle to follow.

If ever the actuals approached this simulation, which is doubtful at a reasonable rate of conversion to BEV/PHEV - then solutions are available in catalytic converters tweaked for acetaldehyde and formaldehyde. What is not discussed is the study also shows an average reduction of 80% compared to gasoline in some 30 different pollutants. Table 1, 2020 baseline.

the study probably focussed on L.A. because its particular topography and micro-climate make it much more prone to smog formation than most other places in the US. In the South-East, for example, locally high concentrations of NOx are more readily dispersed over a much larger area by the prevalent weather patterns.

The reason for the additional NOx from E85 combustion is that flex-fuel systems need to be optimized for the lowest octane fuel, i.e. gasoline. The anti-knock system will advance ignition timing to improve thermodynamic efficiency when using E85, to compensate a little for its relatively low energy density. This increases peak combustion temps and hence, engine-out NOx. Meanwhile, raw CO and HC emissions are the same or lower, so the three-way catalyst cannot clean up the extra NOx.

In other words, if the marginally higher tailpipe emissions of NOx really amount to a population health problem in places like LA, then manufacturers can compensate by easing off on the ignition advance for vehicles sold in states subject to CARB emissions, at the expense of slightly worse fuel economy on E85 only.

Canada supplies 15% of the natural gas consumed in the US, and this is 60% of total Canadian production. If you have to import natural gas, I think calling the US the Middle East of natural gas is erroneous.

Well as long as we are off topic about natural gas: methane generation from biomass, municipal waste and Shi/eer "poop" is another potential source, so we don't need to just get it from the ground (unless the ground is over a landfill).

Internal combustion engines(ICE) are bad for people. Its time to put research for electrical energy storage & renewable energy sources as our top priority, start using mobile electric motors near people, & get ICE away from people. It's time & way past time. You guys are so silly & uncompassionate as you debate which ICE forms will kill the most inner city kids living near freeways.

I think a realistic view is an affordable and viable path to getting where we want to go, from where we are now. That is a general way of saying that the world is not going to stop everything, scrap every engine, retool and start all over from scratch because one person thinks the way things are now is "silly".

Air pollution is not killing anyone in the US except in computer models. The days of killer smog are long gone. The irony is that indoor air pollution has increased because of conservation measures. Hot weather increases respiratory-related deaths and hospitalizations which happens to correspond to temperature inversions that trap smog.

No it is second hand smoke, no it is radon, no coal plants. What ever happened to real public heath problems like cholera?

The American Lung Association of the Upper Midwest is a strong supporter of E85, which we conclude is a cleaner-burning alternative to gasoline with long-term benefits.

Our specific comments are as follows:

·The study assumes that ALL vehicles will be operating on E85 in 2020 - effectively an impossible scenario by all accounts. E85 was never intended as a complete gasoline replacement, and will only be capable of achieving a portion of the total US fuel demand. Additionally, the areas of the county where this study demonstrates E85 to have the most harmful effects are where E85 is not currently manufactured or sold, making them the least likely areas of concern.

· Air toxics lifecycle emissions modeling published in the Journal of Air and Waste Management Association which showed that while ethanol-based fuels may increase emissions of a pollutant called aldehydes, it reduces two much more serious air pollutants linked to cancer, benzene and butadiene.

· Many noted experts, including Michael Wang of Argonne National Laboratory, widely considered the leading expert in modeling lifecycle emissions, agree that using E85 instead of gasoline can reduce overall lifecycle emissions and the associated cancer risk associated with gasoline powered vehicles.

· Carbon dioxide emissions associated with global climate change were also not considered -- for which biofuels provide the biggest benefit. Our estimates indicate a typical E85 user could prevent up to 4 tons of CO2 lifecycle emissions from entering our atmosphere each year.